In OmegaWiki, when an image is added, it is attached to a particular concept, and is then displayed for all words representing that concept. Compared to Wiktionary where you would need to add an image of a concept for each page of each synonym, and for each page of each language, there is a lot of redundant work that is avoided.

As of today, there are about 47.000 concepts in OmegaWiki. It means that more than 2% of them have an image. It is not clear what percentage can be reached. Several concepts are abstract (feelings, reasonings), and other are verbs or names of languages and are hard to illustrate.

I find it particularly useful when a word with different meanings has different images, such as vampire, bluebottle, Mars, Venus, etc. Also interesting is to find an illustration for abstract concepts. This is sometimes possible: season, wake up or cheapskate.